A process for the production of 1,4-butanediol from maleic anhydride by hydrogenation

Abstract

The present application relates to the field of chemical raw material processing, and particularly to a method for preparing 1,4-butanediol by hydrogenation of maleic anhydride, which uses maleic anhydride as raw material and a bimetallic copper-based catalyst Cu-xM / SiO2 as catalyst to generate 1,4-butanediol in one step through catalytic hydrogenation under mild conditions. The bimetallic copper-based catalyst Cu-xM / SiO2 uses silicon dioxide as carrier, copper particles as active component, and adds a second metal component M to obtain a supported bimetallic copper-based catalyst Cu-xM / SiO2 after hydrogen reduction, wherein the loading amount of the active component copper is 20 wt%-40 wt%, the second component metal M is one or a mixture of two or more of Mo, Fe, Zr, Zn or Al, and x is the molar ratio of M to Cu, which is 0.01-0.25:1.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical raw material processing, in particular to a method for preparing 1,4-butanediol by hydrogenation of maleic anhydride. BACKGROUND

[0002] 1,4-butanediol (BDO) is an important chemical in industry, which can be converted into gamma-butyrolactone (GBL), tetrahydrofuran (THF), GBL is a raw material for producing 2-pyrrolidone and N-methyl pyrrolidone products, from which a series of high value-added products such as vinyl pyrrolidone, polyvinyl pyrrolidone, etc. can be widely used in the fields of pesticides, medicines and cosmetics, etc. THF is an important organic solvent, and polytetramethylene glycol ether (PTMEG) obtained by polymerization is a basic raw material for producing high-elasticity spandex (lycra fiber). It is also a basic raw material for producing polybutylene adipate (PBAT) and polybutylene succinate (PBS) and polybutylene terephthalate products, among which PBT plastic is one of the five most promising engineering plastics.

[0003] At present, the large-scale industrial production of BDO still relies on the traditional petrochemical route, such as Reppe method, which accounts for 53% of the total global production capacity. It is well known that the raw material of Reppe method is acetylene and formaldehyde, and the production of one of the raw materials, acetylene, depends on the calcium carbide industry with high energy cost. At the same time, acetylene also has the risk of explosion, which is relatively high.

[0004] Maleic anhydride can be obtained by oxidation of biomass raw materials such as furfural and 5-hydroxymethyl furfural, therefore, it is considered as an environmentally friendly and sustainable way to obtain 1,4-butanediol by selective hydrogenation of maleic anhydride. Maleic anhydride is easy to be hydrogenated to GBL under the action of copper-based catalyst, and GBL can be further hydrogenated to obtain two products, BDO and THF. The two reactions are competitive, and BDO can also be further dehydrated to generate THF, which increases the difficulty of selective hydrogenation of maleic anhydride to BDO. So far, most of the products obtained by selective hydrogenation of maleic anhydride reported in the literature are GBL, and there is only one article reported in the literature that BDO is directly obtained by selective hydrogenation of maleic anhydride, the yield of BDO is only about 65%, and the reaction conditions are relatively harsh, the reaction requires 230 ℃ and 9 MPa hydrogen pressure (Ind. Eng. Chem. Res., 1998, 37, 759-769), and the yield still has a large space for improvement. SUMMARY

[0005] The purpose of the present application is to solve the problems in the background art, and to provide a method for preparing 1,4-butanediol by hydrogenation of maleic anhydride.

[0006] The above technical purposes of the present application are realized by the following technical solutions.

[0007] A method for preparing 1,4-butanediol by hydrogenation of maleic anhydride, using maleic anhydride as raw material and a bimetallic copper-based catalyst Cu-xM / SiO2 as catalyst, to generate 1,4-butanediol in one step through catalytic hydrogenation under mild conditions.

[0008] As preferred, the bimetallic copper-based catalyst Cu-xM / SiO2 uses silica as a carrier, copper particles as an active component, and a second metal component M, and after hydrogen reduction, a supported bimetallic copper-based catalyst Cu-xM / SiO2 is obtained, wherein the loading amount of the active component copper is 20 wt%-40 wt%, the second component metal M is one or a mixture of two or more of Mo, Fe, Zr, Zn or Al, x is the molar ratio of M to Cu, and the ratio is 0.01-0.25:1.

[0009] As preferred, the bimetallic copper-based catalyst Cu-xM / SiO2 uses a hydrothermal method to load the active component copper on silica and is generated after hydrogen reduction, and the specific preparation includes the following steps:

[0010] a. Dissolve the metal copper and the precursor of M in deionized water in a certain proportion to form a solution, and then add a certain amount of ammonium chloride to the solution; the copper precursor is copper nitrate, copper chloride or copper sulfate, the M precursor is the nitrate of M or the chloride of M, the proportion is M / Cu=0.01-0.25:1, and the amount of ammonium chloride added is 3-8:1 in molar ratio with the copper precursor;

[0011] b. Adjust the pH of the mixed solution prepared in step a to 9-14 with an alkaline agent, and then add a silicon source to the mixed solution after sufficient stirring, and then perform aging treatment; the alkaline agent is ammonia water, ammonium carbonate, or a combination of the two, and the silicon source is one of sodium silicate, silica sol, tetraethyl orthosilicate, white carbon black, and silica sol;

[0012] c. Transfer the mixed solution of step b to a hydrothermal kettle and perform hydrothermal treatment at a temperature of 150-200°C for 40-48h;

[0013] d. Place the solid obtained in step c in a vacuum oven for drying, and then obtain the bimetallic copper-based catalyst Cu-xM / SiO2 precursor after calcination; the drying temperature is 60-120°C, the drying time is 12-24h, the calcination temperature is 400-600°C, and the calcination time is 2-8h;

[0014] e. The bimetallic copper-based catalyst Cu-xM / SiO2 precursor obtained in step d is reduced under a hydrogen flow to obtain the bimetallic copper-based catalyst Cu-xM / SiO2; the hydrogen flow rate is 30-150 mL / min, the hydrogen purity is 99.999%, the reduction temperature is 200-450℃, and the reduction time is 0.5-4 h.

[0015] Preferably, maleic anhydride is hydrogenated to prepare 1,4-butanediol under the catalysis of a bimetallic copper-based catalyst Cu-xM / SiO2, specifically including the following steps:

[0016] 1) Maleic anhydride, bimetallic copper-based catalyst Cu-xM / SiO2, and solvent are added together to an electromagnetically stirred high-pressure reactor. The weight / volume ratio of maleic anhydride to solvent is 100-1000 mg / 7-12 mL, and the mass ratio of maleic anhydride to bimetallic copper-based catalyst Cu-xM / SiO2 is 1:0.2-1.

[0017] 2) The reaction solvent for the catalytic hydrogenation of maleic anhydride to prepare 1,4-butanediol is one or a mixture of methanol, 1,4-dioxane, DMF and THF.

[0018] 3) Hydrogen gas is introduced into the reactor and the temperature is raised to the target temperature for hydrogenation reaction. The hydrogen pressure is 3-6 MPa, the hydrogenation reaction temperature is 160-250℃, and the reaction time is 2-14 h. After the reaction is completed, the gas is detected by gas chromatography.

[0019] In summary, compared with existing technologies, this invention has advantages such as good reactivity, high product selectivity, and environmental friendliness. Under optimized conditions, the conversion rate of maleic anhydride reaches 100%, and the selectivity of 1,4-butanediol reaches over 90%. The Cu particles are uniformly distributed, with a large specific surface area and pore volume, exhibiting high catalytic activity. The catalyst preparation process is simple, the reaction conditions are relatively mild, and it is easy to industrialize. Furthermore, the reaction process is environmentally friendly, providing more possibilities for the green and efficient preparation of 1,4-butanediol. Detailed Implementation

[0020] The following specific embodiments are merely illustrative of the present invention and are not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to these embodiments without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of the present invention.

[0021] A method for preparing 1,4-butanediol by hydrogenation of maleic anhydride is disclosed, which uses maleic anhydride as raw material and a bimetallic copper-based catalyst Cu-xM / SiO2 as catalyst. Under mild conditions, 1,4-butanediol is generated in one step by catalytic hydrogenation.

[0022] The bimetallic copper-based catalyst Cu-xM / SiO2, with silica as the carrier, copper particles as the active component, and the addition of a second metal component M, after hydrogen reduction, obtains a supported bimetallic copper-based catalyst Cu-xM / SiO2, wherein the loading amount of the active component copper is 20 wt% to 40 wt%, the second component metal M is one or a mixture of two or more of Mo, Fe, Zr, Zn or Al, x is the molar ratio of M to Cu, and the ratio is 0.01 to 0.25:1.

[0023] Maleic anhydride is prepared into 1,4-butanediol under the catalysis of the bimetallic copper-based catalyst Cu-xM / SiO2, and specifically includes the following steps:

[0024] 1) Maleic anhydride, a bimetallic copper-based catalyst Cu-xM / SiO2, and a solvent are added together into an electromagnetic stirring high-pressure reaction kettle, the weight / volume ratio of the maleic anhydride to the solvent is 100 to 1000 mg / 7 to 12 mL, and the mass ratio of the use amount of the maleic anhydride to the bimetallic copper-based catalyst Cu-xM / SiO2 is 1:0.2 to 1.

[0025] 2) The reaction solvent for preparing 1,4-butanediol by catalytic hydrogenation of maleic anhydride is a mixed solvent of one or several of methanol, 1,4-dioxane, DMF, and THF.

[0026] 3) Hydrogen is filled into the kettle, the target temperature is raised for hydrogenation reaction, the hydrogen pressure is 3 to 6 MPa, the hydrogenation reaction temperature is 160 to 250°C, and the reaction time is 2 to 14 h; after the reaction is completed, gas chromatography is used for detection.

[0027] Example 1

[0028] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0029] a, 3.14 g of Cu(NO3)2·3H2O and 0.125 g of (NH3)6Mo7O 24 ∙4H2O are respectively dissolved in deionized water to obtain a mixed solution, and 2.78 g of ammonium chloride is added to the mixed solution.

[0030] b, 10 mL of concentrated ammonia water is slowly added to the above mixed solution under stirring.

[0031] c, 2.24 g of silica sol is added to the mixed solution obtained in step b, and stirring is performed at room temperature for 4 h to obtain a precursor mixed solution.

[0032] d, the precursor mixed solution obtained in step c is transferred to a hydrothermal kettle, and hydrothermal treatment is performed at 190°C for 48 h.

[0033] e, The mixture obtained in step d is filtered, washed, and dried in a vacuum oven at 60 °C for 12 h, and calcined in a tube furnace at 450 °C for 4 h to obtain a catalyst precursor.

[0034] f, The catalyst precursor obtained in step d is placed in a hydrogen atmosphere, reduced at 350 °C for 2 h to obtain a catalyst Cu-0.05Mo / SiO2.

[0035] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0036] Take 200 mg of the above catalyst and add 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass in pure hydrogen gas with a pressure of 6.0 MPa and a purity of 99.999%, and carry out catalytic hydrogenation reaction under electromagnetic stirring at 200 °C for 10 h. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography. The conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol with a selectivity of 90%. It can be seen that the copper-based catalyst prepared in Example 1 exhibits excellent catalytic activity and product selectivity in the continuous hydrogenation reaction of maleic anhydride.

[0037] Example 2

[0038] (I) Preparation of Cu-0.02Mo / SiO2 catalyst

[0039] a, Dissolve 3.14 g of Cu(NO3)2·3H2O and 0.048 g of (NH3)6Mo7O 24 ·4H2O in deionized water to obtain a mixed solution, and add 1.60 g of ammonium chloride to the mixed solution.

[0040] b, Slowly add 10 mL of concentrated ammonia water to the above mixed solution under stirring.

[0041] c, Add 2.24 g of silica sol to the mixed solution obtained in step b, and stir at room temperature for 4 h to obtain a precursor mixed solution.

[0042] d, Transfer the precursor mixed solution obtained in step c to an autoclave, and hydrothermal treatment at 190 °C for 48 h.

[0043] e, The mixture obtained in step d is filtered, washed, and dried in a vacuum oven at 60 °C for 12 h, and calcined in a tube furnace at 450 °C for 4 h to obtain a catalyst precursor.

[0044] f, The catalyst precursor obtained in step d is placed in a hydrogen atmosphere, reduced at 350 °C for 2 h to obtain a catalyst Cu-0.02Mo / SiO2.

[0045] (ii) Hydrogenation of maleic anhydride to 1,4-butanediol catalyzed by Cu-0.05Mo / SiO2 catalyst

[0046] The copper-based catalyst prepared above was used in the hydrogenation reaction of maleic anhydride as in Example 1, and the conversion of maleic anhydride was 100% and the selectivity of 1,4-butanediol was 57.7%.

[0047] Example 3

[0048] (i) Preparation of Cu-0.25Mo / SiO2 catalyst:

[0049] a. 3.14 g of Cu(NO3)2·3H2O and 0.625 g of (NH3)6Mo7O 24 24·4H2O were dissolved in deionized water to obtain a mixed solution, and 4.28 g of ammonium chloride was added to the mixed solution.

[0050] b. 10 mL of concentrated ammonia was slowly added to the above mixed solution under stirring.

[0051] c. 2.24 g of silica sol was added to the mixed solution obtained in step b, and the mixture was stirred at room temperature for 4 h to obtain a precursor mixed solution.

[0052] d. The precursor mixed solution obtained in step c was transferred to an autoclave, and hydrothermal treatment was carried out at 190 °C for 48 h.

[0053] e. The mixed solution obtained in step d was filtered, washed, and placed in a vacuum oven at 60 °C for drying for 12 h, and then calcined in a tube furnace at 450 °C for 4 h to obtain a catalyst precursor.

[0054] f. The catalyst precursor obtained in step d was placed in a hydrogen atmosphere, and reduction was carried out at 350 °C for 2 h to obtain a catalyst Cu-0.25Mo / SiO2.

[0055] (ii) Hydrogenation of maleic anhydride to 1,4-butanediol catalyzed by Cu-0.25Mo / SiO2 catalyst

[0056] The copper-based catalyst prepared above was used in the hydrogenation reaction of maleic anhydride as in Example 1, and the conversion of maleic anhydride was 100% and the selectivity of 1,4-butanediol was 57.7%.

[0057] Example 4

[0058] (i) Preparation of Cu-0.05Fe / SiO2 catalyst:

[0059] a, 3.14 g Cu(N03)2-3H20 and 0.27 g Fe(N03)3-9H20 were dissolved in deionized water respectively to obtain a mixed solution, and 2.78 g of ammonium chloride was added to the mixed solution.

[0060] b, 10 mL of concentrated ammonia was slowly added to the above mixed solution under stirring.

[0061] c, 2.24 g of silica sol was added to the mixed solution obtained in step b, and stirred at room temperature for 4 h to obtain a precursor mixed solution.

[0062] d, the precursor mixed solution obtained in step c was transferred to an autoclave, and hydrothermal treatment was carried out at 190 °C for 48 h.

[0063] e, the mixed solution obtained in step d was filtered, washed, and placed in a vacuum oven at 60 °C for drying for 12 h, and calcined in a tube furnace at 450 °C for 4 h to obtain a catalyst precursor.

[0064] f, the catalyst precursor obtained in step d was placed in a hydrogen atmosphere and reduced at 350 °C for 2 h to obtain a catalyst Cu-0.05Fe / Si02.

[0065] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Fe / Si02 catalyst

[0066] The application of the above prepared copper-based catalyst in the hydrogenation reaction of maleic anhydride was the same as in Example 1, and the conversion rate of maleic anhydride was 100%, and the selectivity of 1,4-butanediol was 69.5%.

[0067] Example 5

[0068] (I) Preparation of Cu-0.03Zr / Si02 catalyst:

[0069] a, 3.14 g of Cu(N03)2-3H20 and 0.17 g of Zr(N03)4-5H20 were dissolved in deionized water respectively to obtain a mixed solution, and 2.78 g of ammonium chloride was added to the mixed solution.

[0070] b, 10 mL of concentrated ammonia was slowly added to the above mixed solution under stirring.

[0071] c, 2.24 g of silica sol was added to the mixed solution obtained in step b, and stirred at room temperature for 4 h to obtain a precursor mixed solution.

[0072] d, the precursor mixed solution obtained in step c was transferred to an autoclave, and hydrothermal treatment was carried out at 190 °C for 48 h.

[0073] e, The mixture obtained in step d is filtered, washed, and dried in a vacuum oven at 60 °C for 12 h, and calcined in a tube furnace at 450 °C for 4 h to obtain the catalyst precursor.

[0074] f, The catalyst precursor obtained in step d is reduced under hydrogen atmosphere at 350 °C for 2 h to obtain the catalyst Cu-0.03Zr / SiO2.

[0075] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.03Zr / SiO2 catalyst

[0076] The copper-based catalyst prepared above is applied in the hydrogenation reaction of maleic anhydride as in Example 1, and the conversion rate of maleic anhydride is 100% and the selectivity of 1,4-butanediol is 19.3%.

[0077] Example 6

[0078] (I) Preparation of Cu-0.05Mo / SiO2 catalyst

[0079] The preparation method is the same as that in Example 1.

[0080] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0081] Take 200 mg of the above catalyst and add it to 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass in pure hydrogen gas with a pressure of 4.0 MPa and a purity of 99.999%, and carry out catalytic hydrogenation reaction under electromagnetic stirring at 200 °C for 10 h. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography, the conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol, and the selectivity is 51.9%.

[0082] Example 7

[0083] (I) Preparation of Cu-0.05Mo / SiO2 catalyst

[0084] The preparation method is the same as that in Example 1.

[0085] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0086] Take 200 mg of the above catalyst into 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass pure hydrogen gas with a pressure of 3.0 MPa and a purity of 99.999% at 200 ℃ under electromagnetic stirring for 10 h of catalytic hydrogenation reaction. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography, the conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol, and the selectivity is 43.4%.

[0087] Example 8

[0088] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0089] The preparation method is the same as that of Example 1.

[0090] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0091] Take 200 mg of the above catalyst into 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass pure hydrogen gas with a pressure of 5.0 MPa and a purity of 99.999% at 210 ℃ under electromagnetic stirring for 10 h of catalytic hydrogenation reaction. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography, the conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol, and the selectivity is 73.3%.

[0092] Example 9

[0093] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0094] The preparation method is the same as that of Example 1.

[0095] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0096] Take 200 mg of the above catalyst into 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass pure hydrogen gas with a pressure of 5.0 MPa and a purity of 99.999% at 200 ℃ under electromagnetic stirring for 8 h of catalytic hydrogenation reaction. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography, the conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol, and the selectivity is 65.8%.

[0097] Example 10

[0098] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0099] The preparation method is the same as that of Example 1.

[0100] (II) Hydrogenation of maleic anhydride to prepare 1,4-butanediol under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0101] Take 200 mg of the above catalyst and add it to 10 mL of DMF, then add 0.2 g of maleic anhydride, and pass in pure hydrogen gas with a pressure of 5.0 MPa and a purity of 99.999%, and carry out catalytic hydrogenation reaction under electromagnetic stirring at 200°C for 10 h. After the hydrogenation reaction is completed, separate the product from the catalyst, and analyze the product by gas chromatography. The conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol with a selectivity of 82%.

[0102] Example 11

[0103] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0104] The preparation method is the same as that of Example 1.

[0105] (II) Hydrogenation of maleic anhydride to prepare 1,4-butanediol under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0106] Take 200 mg of the above catalyst and add it to 10 mL of methanol, then add 0.2 g of maleic anhydride, and pass in pure hydrogen gas with a pressure of 5.0 MPa and a purity of 99.999%, and carry out catalytic hydrogenation reaction under electromagnetic stirring at 200°C for 10 h. After the hydrogenation reaction is completed, separate the product from the catalyst, and analyze the product by gas chromatography. The conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol with a selectivity of 53%.

[0107] Example 12

[0108] (I) Preparation of Cu-0.05Mo / SiO2 catalyst:

[0109] The preparation method is the same as that of Example 1.

[0110] (II) Hydrogenation of maleic anhydride to prepare 1,4-butanediol under the catalysis of Cu-0.05Mo / SiO2 catalyst

[0111] Take 100 mg of the above catalyst into 10 mL of 1,4-dioxane, then add 0.2 g of maleic anhydride, and pass pure hydrogen gas with a pressure of 5.0 MPa and a purity of 99.999% at 200°C under electromagnetic stirring for 10 h. After the hydrogenation reaction is completed, the product is separated from the catalyst, and the product is analyzed by gas chromatography. The conversion rate of maleic anhydride is 100%, and the obtained product is 1,4-butanediol with a selectivity of 52.5%.

[0112] Comparative Example 1

[0113] (I) Preparation of copper-based catalyst Cu / SiO2 without adding a second component metal as follows:

[0114] a. Dissolve 3.14 g of Cu(NO3)2·3H2O in deionized water to obtain a mixed solution, and add 2.78 g of ammonium chloride to the mixed solution.

[0115] b. Slowly add 10 mL of concentrated ammonia to the above mixed solution under stirring.

[0116] c. Add 2.24 g of silica sol to the mixed solution obtained in step b, and stir at room temperature for 4 h to obtain a precursor mixed solution.

[0117] d. Transfer the precursor mixed solution obtained in step c to an autoclave, and hydrothermal treatment at 190°C for 48 h.

[0118] e. Filter and wash the mixed solution obtained in step d, and place it in a vacuum oven at 60°C for drying for 12 h, and calcine in a tube furnace at 450°C for 4 h to obtain a catalyst precursor.

[0119] f. Place the catalyst precursor obtained in step d in a hydrogen atmosphere, and reduce at 350°C for 2 h to obtain a catalyst Cu / SiO2.

[0120] (II) Hydrogenation of maleic anhydride to prepare 1,4-butanediol under the catalysis of Cu / SiO2 catalyst

[0121] The copper-based catalyst prepared in Comparative Example 1 is applied in the hydrogenation reaction of maleic anhydride, and the conversion rate of maleic anhydride is 100% and the selectivity of 1,4-butanediol is 41.1%.

[0122] Comparative Example 2

[0123] (I) Preparation of catalyst Mo / SiO2 without adding a copper component as follows:

[0124] a. Dissolve 0.075 g of (NH3)6Mo7O 24* 4H2O is dissolved in deionized water to obtain a mixed solution, and 2.78 g of ammonium chloride is added to the mixed solution.

[0125] b. 10 mL of concentrated ammonia is slowly added to the above mixed solution under stirring.

[0126] c. 2.24 g of silica sol is added to the mixed solution obtained in step b, and the mixed solution is stirred at room temperature for 4 h to obtain a precursor mixed solution.

[0127] d. The precursor mixed solution obtained in step c is transferred to an autoclave, and hydrothermal treatment is carried out at 190 °C for 48 h.

[0128] e. The mixed solution obtained in step d is filtered, washed, and dried in a vacuum oven at 60 °C for 12 h, and then calcined in a tube furnace at 450 °C for 4 h to obtain a catalyst precursor.

[0129] f. The catalyst precursor obtained in step d is placed in a hydrogen atmosphere, and reduction is carried out at 350 °C for 2 h to obtain a catalyst Mo / SiO2.

[0130] (II) Preparation of 1,4-butanediol by hydrogenation of maleic anhydride under the catalysis of Mo / SiO2 catalyst

[0131] The catalyst prepared in Comparative Example 2 is applied in the hydrogenation reaction of maleic anhydride, and the results are as follows: the conversion rate of maleic anhydride is 93%, and the selectivity of 1,4-butanediol is 10.1%.

[0132] The copper-based catalysts prepared in the above examples are used for the performance test of maleic anhydride hydrogenation, and the results are shown in Table 1 below:

[0133] Table 1 Reaction performance of copper-based catalysts for maleic anhydride hydrogenation

[0134]

[0135] The above examples are only for further illustration of the present application, and do not limit the present application. Any equivalent implementation of the present application should be included in the scope of the claims of the present application.

Claims

1. A process for the production of 1,4-butanediol from the hydrogenation of maleic anhydride, characterized in that, Maleic anhydride is used as raw material, and a bimetallic copper-based catalyst Cu-xM / SiO2 is used as catalyst to generate 1,4-butanediol through catalytic hydrogenation under mild conditions, wherein the bimetallic copper-based catalyst Cu-xM / SiO2 uses silica as carrier, copper particles as active component, and a second metal component M is added to obtain a supported bimetallic copper-based catalyst Cu-xM / SiO2 after hydrogen reduction, wherein the loading amount of the active component copper is 20 wt%-40 wt%, the second component metal M is Mo, and x is the molar ratio of M to Cu, which is 0.05:

1. The specific steps for preparing 1,4-butanediol are as follows: 1) Maleic anhydride, a bimetallic copper-based catalyst Cu-xM / SiO2 and a solvent are added into an electromagnetic stirring high-pressure reaction kettle, the weight / volume ratio of maleic anhydride to solvent is 100-1000 mg / 7-12 mL, and the mass ratio of the use amount of maleic anhydride to the bimetallic copper-based catalyst Cu-xM / SiO2 is 1:0.2-1; the bimetallic copper-based catalyst Cu-xM / SiO2 is prepared by loading the active component copper on silica through a hydrothermal method and then reducing with hydrogen; 2) The reaction solvent for preparing 1,4-butanediol through catalytic hydrogenation of maleic anhydride is one or a mixture of several of methanol, 1,4-dioxane, DMF and THF; 3) Hydrogen is filled into the kettle, the target temperature is raised for hydrogenation reaction, the hydrogen pressure is 5 MPa or 6 MPa, the purity is 99.999%, the hydrogenation reaction temperature is 200 DEG C, and the reaction time is 10 h; after the reaction is completed, gas chromatography is used for detection.

2. The method of claim 1, wherein the maleic anhydride is hydrogenated to produce 1,4-butanediol. The bimetallic copper-based catalyst Cu-xM / SiO2 is prepared through the following steps: a. Dissolve the precursors of copper and M in deionized water in a certain proportion to form a solution, and then add a certain amount of ammonium chloride to the solution; the precursor of copper is copper nitrate, copper chloride or copper sulfate, the precursor of M is the nitrate of M or the chloride of M, the proportion is M / Cu=0.01-0.25:1, and the amount of ammonium chloride added is 3-8:1 in terms of molar ratio with the precursor of copper; b. Adjust the pH of the mixed solution prepared in step a to 9-14 with an alkaline agent, fully stir to obtain a mixed solution, add a silicon source to the mixed solution, and then perform aging treatment; the alkaline agent is one or a combination of ammonia and ammonium carbonate, and the silicon source is one of sodium silicate, silica sol, tetraethyl orthosilicate, white carbon black and silica sol; c. Transfer the mixed solution of step b to a hydrothermal kettle, and perform hydrothermal treatment at a temperature of 150-200 DEG C for 40-48 h; d. Dry the solid obtained in step c in a vacuum oven, and obtain the precursor of the bimetallic copper-based catalyst Cu-xM / SiO2 after calcination; the drying temperature is 60-120 DEG C, the drying time is 12-24 h, the calcination temperature is 400-600 DEG C, and the calcination time is 2-8 h; e、 reducing the bimetallic copper-based catalyst Cu-xM / SiO2 precursor obtained in the step d under a hydrogen stream to obtain a bimetallic copper-based catalyst Cu-xM / SiO2; the hydrogen flow rate is 30-150 mL / min, the hydrogen purity is 99.999%, the reduction temperature is 200-450°C, and the reduction time is 0.5-4 h.

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